import javax.net.ServerSocketFactory;

class DeleteThis
extends ServerSocketFactory
{
	
	public java.net.ServerSocket createServerSocket(int a)
	{ return null;}
	
	public java.net.ServerSocket createServerSocket(int a,int b)
	{ return null;}
	
	public java.net.ServerSocket createServerSocket(int a,int b, java.net.InetAddress addr)
	{ return null;}
	
    public static void main(String args[])
    {
    	new DeleteThis();
    	System.out.println("OK");
    }
}